Heart Rate Zone Calculator
Find your 5 heart rate training zones based on age and resting heart rate. Train smarter — know when you're burning fat, building endurance, or hitting peak power.
Two Methods, One Goal
The standard method uses simple percentages of your max heart rate (220 − age). The Karvonen method factors in your resting heart rate for more personalized zones. If you know your resting HR (measure it first thing in the morning), Karvonen gives slightly better results — especially for fit individuals with low resting rates.
Which Zone Should You Train In?
That depends on your goals. For general fitness and fat burning, spend most of your time in Zones 2-3. For performance and speed, mix in Zone 4-5 intervals. The "80/20 rule" used by elite endurance athletes suggests 80% of training should be in Zones 1-2, with 20% in Zones 4-5. Zone 3 is sometimes called the "gray zone" — hard enough to tire you out but not hard enough to trigger strong adaptations.
⚠️ Medical Disclaimer
This tool provides estimates for informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making health decisions. Results may vary based on individual factors not captured by this calculator.